Gray literature may be cited like any other paper although with the caveat mentioned before that it is considered less "official" and reliable than peer-reviewed scientific papers. There are many sources for gray literature.
Possible sources of scientific and technical gray literature:
Watch this video for additional tips.
-adapted from BEE 2600 tutorial
What are technical reports? Technical reports present facts and conclusions about technological designs and projects. Typically, a technical report includes research about concepts as well as graphical depictions of designs and data. A technical report also follows a strict organization. Thus, when engineers read it, they can quickly locate the information they need.1
A technical report is a form of grey literature: Reports or documents produced by academia, government, industry or nonprofit organizations describing their work, proposals and/or the challenges they face. Grey literature is copyrighted like most other published work, but it usually is not distributed by commercial publishers the way a book or periodical would be but rather by the authoring organization itself. The organization that publishes the report is usually considered the 'author' (even if named individuals are credited within the report).
Some sources of technical reports:
Not all websites are created equal! Major nongovernmental organizations and various scholarly associations can be rich and authoritative websites, especially for the kind of grey literature not published in mainstream scholarly journals (including white papers, evaluation reports, training materials, and the like). Below are a few useful places to start.
Working papers are preliminary works, released to share ideas or invite discussion and feedback, often prior to the submission of a paper to a peer-reviewed journal or conference. Economists have traditionally relied on working papers as a method for the timely and informal communication of recent research findings.